naka ushiro, yukino bijin (umamusume), umamusume, commentary request, highres, 1girl, animal ears, blue one-piece swimsuit, blush, braid, breasts, brown eyes, brown hair, clothes pull, collarbone, covered navel, flying sweatdrops, horse ears, horse girl, horse tail, jacket, long sleeves, looking at viewer, medium breasts, navel, nose blush, one-piece swimsuit, open mouth, red jacket, red shorts, school swimsuit, shorts, shorts pull, simple background, solo, swimsuit, tail, tracen training uniform, white background